Communications Sector 2

Communications Sector 2
Step into the next room and call the lift to you. Ride the lift to the next level and ready your shotgun to take down the imp that drops down in front of you. Head into the next hall, but watch out for the pair of Z-SECs guarding the area. There's some armor and health under the walkway you can grab before picking up the PDA of Ben Wolfe.

Open up the next door and you'll immediately have to deal with a pair of Z-SECs down the hall to your left. You can lure them up to the doorway for a pair of easy kills, but you'll need to watch out for the cacodemon that shows up later. Go through the door to the left and take out another Z-SEC that's around the corner to the right. There's a storage locker you can open with the code 246. Grab the gear, and then activate the sentry bot by using the control panel in the room.

Follow the sentry bot out of the room and through the doorway to the left. Keep the bot in front of you and it'll clear out all enemies in your path (though you should still watch your back). Eventually, the sentry will lead you to another locked door. If your sentry bot dies, you can backtrack and summon another one to continue leading you through the halls. When the sentry bot has finished its duties, it'll rest in front of an elevator. Step into the elevator and take it to "Satellite Control."

Head down the hall at the top of the elevator to enter the Satellite Control Center. Grab the PDA of Rob Finch and activate the computer terminal on the other side of the counter to start sending the transmission (whether you choose to send or cancel is up to you). When you've done so, backtrack to the elevator and take it down to "Maintenance."

Just to the right of the elevator's exit is a Z-SEC, and further around the corner is an imp. Keep going down the hall to run into two more Z-SECs before you reach the level's exit. You can head into the room to the left to grab some shotgun ammo and health, but watch out for an imp that drops in front of you when you exit the room. When you're ready, exit the level to reach the next stage.